Clutch for leather-stretching machines.



No. 852,800. PATBNTED MAY 7,1907,

' E. L. PO'ST. I

' CLUTCH FOR LEATHER STRETGHING MACHINES. grrpmmmn FILED NOV.19, 1996.

Hill I WI 8858 I I 7 7 ATTORNEYS UNITE STATES PATNT ()FFTQF.

CLUTCH FOR LEATHER-STRETCHING MACHINES.

Specification of Letters Patent.

Patented May 7, 1907.

Application filed November 19, 1906. Serial No. 343,996.

To a whom it may concern.-

l Be it known that I, EZRA L. Pos'r, a citizen of the United States, residing at Walling- I ford, in the county of New Haven and State of Connecticut, have invented certain new and useful Improvements in Clutches for Leather-Stretching Machines, of which the following is a specification, such as will enable those skilled in the art to which it appertains to make and use the same.

1; This invention relates to clutches for leather stretching machines and is an improvement on that described and claimed in Letters Patent of the United States granted to me June 26, 1906, No. 824,129; and the object of the invention is to provide a clutch of this class with improved means for locking the movable or operative aw in position for usewhen the machine is in operation; a further object being to provide a clutch of the class specified which will securely hold the leather to be stretched without cutting, tearing or injuring the same, and which will not allow the leather to slip therethrough and which may be easily and conveniently manipulated.

The invention is fully disclosed in the following specification, of which the accompanying drawing forms a part, in which the separate parts of my improvement are desig nated by suitable reference characters in each of the views, and in which Figure 1 is a side view of a leather clutch of the class specified constructed according to my invention; and, Fig. 2 a rear end view of a portion thereof with part of the construction in section.

In the drawing forming part of this specification, I have shown at a a clutch which is pivoted on a base plate I) which is slidably mounted on a bar 0, said bar being provided with a pivoted dog d which operates in connection with ratchet teeth 0 formed in the central longitudinal part of the bar 0 so as to prevent the clutch a from moving forward.

when in operation while permitting it to be moved backward when desired. The main parts of the clutch a, the base plate b to which it is pivoted, the bar a and dog d are all the same in construction and operation as in my prior patent hereinbefore referred to; and said clutch is free to swing in a horizontal plane on the plate I), and in practice the bar 0 is pivoted to the frame of the leather stretching machine and is also adapted to swing in a horizontal plane, and said clutch may be ad- I justed to any desired position on the bar 0 by means of the dog d. The clutch a is also provided with a stationary transverse jaw a and a pivoted jaw a between which the leather to be stretched is placed as shown at e. The clutch a is also provided integrally with the stationary jaw a with a segmental or circularly curved back portion a which extends upwardly and forwardly and to which the movable jaw ct is pivoted as shown at a and the movable jaw a is provided with a yokeshaped arm (1, having an extended handle a all of these parts being also of the same construction and operation as in my prior patent hereinbefore referred to.

The invention which constitutes the subject-matter of this application consists of a lock for holding the movable jaw a in operative position as shown in Fig. 1, and for this purpose, I provide the back part a of the clutch with a transversely arranged steel tang f which is secured to or in said part a of the clutch in any desired manner, and mounted on the handle a is a yoke lever 9 having a downwardly directed extension gr provided in its front edge with ratchet teeth g in connection with which the tang f is adapted to operate.

The handle a of the arm a is provided near its front end portion with side lugs or projections h, and the yoke lever g is mounted on said handle forwardly of said side lugs or projections, and pivoted between the side members of the yoke lever g at the top thereof is an arm i having a cam head '6 provided with a segmental bearing surface i and straight bearing surfaces 01* and i and the distance between the bearing surface i and the pivotal point of the cam head i is greater than the radius of the bearing surface i while the distance between the bearing surface i and the pivotal point of the cam head i is greater than that of the bearing surface i and when the arm iis in operating position to hold the movable jaw a in a corresponding position either the bearing surface i or must press upon the handle a of the yokeshaped arm a, and in Fig. 1 of the drawing, the bearing surface i of the head i of the arm i bears on the handle (0 and the movable jaw i is securely locked in operative position and in order to release said jaw the arm z' must be raised and swung forwardly.

It will also be understood that the operation of the arm & depends upon the position of the yoke lever g and the position of this lever may be regulated as may be desired according to the thickness of the leather 0, said lever being raised or lowered so that the tang f may engage with the teeth g at a higher or lower point as may be desired, but in order to move or manipulate the lever g in any way the arm "i must be raised or turned forward so that the surface t of the head i will rest on the forward end of the handle a or on the yoke-shaped. arm a adjacent thereto.

It will be understood that the part a forms the back of the clutch and the tang f is secured to or connected with the back surface thereof, while the stationary jaw f, the movable aw a and the forwardly directed arm of the part a to which the movable jaw a with its yoke-shaped arm a is pivoted constitute the front part of the clutch.

It will also be understood that the movable jaw a is manipulated slowly by the handle a, of the yoke-shaped arm a, and when it is desired to connect the clutch with a sheet of leather the handle a is raised, the leather is secured between the aws a and a and the handle a, depressed, the yoke lever g is then manipulated soas to engage the teeth g with the tang f at the proper point of adjustment, after which the arm i is depressed so that either the bearing surface t or i will press on the handle a in which relation of said parts movable jaw a is locked in operative position.

My invention is not limited to any particularform of the lever 9 nor to any particular method of connecting said lever with the handle a all that is necessary in this connection being to provide a device of this class having an arm t which will operate in connection with the handle 0], said device and the back of the clutch being provided, one with a tang and the other with ratchet teeth, whereby the operation of the parts herein described may be obtained.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent, is

1. A clutch of the class described provided and the other with a tang adapted to operate in connection with said teeth 2. A clutch of the class described provided with a bottom stationary aw and a movable jaw pivoted thereover and provided with a backwardly directed handle, a lever mounted on said handle and movable thereon, an arm pivoted in the top portion of said lever and having a head provided with cam surfaces adapted to bear on said handle, the lower end portion of said lever and the back of the clutch being provided one with ratchet teeth and the other with a tang adapted to operate in connection with said teeth, said handle being provided with side lugs or projections in connection with which said lever operates.

3. A clutch of the class described provided with a stationary bottom jaw and a movable top aw, said movable top aw being provided with a backwardly directed yoke-shaped arm having an extended handle, a yoke lever mounted on said handle and movable thereon, an arm pivoted in the top portion of said lever and provided with a cam head adapted to bear on said handle, the bottom portion of said lever and the back of the clutch being also provided one with ratchet teeth and the other with a tang which operates in connection with said teeth.

In testimony that I claim the foregoing as my invention I have signed my name in pres ence of the subscribing witnesses this 15th day of November 1906.

EZRA L. POST.

Witnesses:

C. E. MULREANY, PAUL BARTELS. 

